Goals for the Year 1981: (a) establishment of a larger panel of cell lines from primary melanomas and premalignant lesions; (b) establishment of the next generation of hybridomas by immunizing mice with primary melanoma and premalignant cells; (c) analysis of the recently established panel of antibodies produced against melanoma cell lines WM 9 (metastatic), WM 51 (familial) and WM 56 (primary); (d) immunochemical characterization of antigens defined by new monoclonal antibodies; (e) to develop a serodiagnostic inhibition assay for detection of melanoma antigens in patients' sera.